1. Field of the Invention
The present invention is concerned with the field of power electronics. In particular it relates to a fast power semiconductor circuit, comprising
(a) a gate turn-off component with an anode and a cathode, which component is in the form of a large-area semiconductor substrate with an anode side and a cathode side opposite the anode side, the anode being arranged on the anode side, and the cathode being arranged together with the gate on the cathode side; and
(b) a drive circuit, which is connected to the gate and the cathode, and generates a current pulse for turning off the component.
Such a circuit is known, for example, from EP-A2-0 228 226.
2. Discussion of Background
The novel, fast, gate turn-off power semiconductor components, which are being used increasingly in power electronics, such as for example the FCTh (Field Controlled Thyristor), the IGBT (Insulated Gate Bipolar Transistor) or the HF-GTO, require short current pulses with very high rates of current rise di/dt for driving.
To be able to achieve such high di/dt values, total values for the inductance L of the drive circuit of only a few nH or, under certain circumstances, of &lt;1 nH are allowed. An arrangement of the drive circuit outside the component housing and a feeding of the control pulses through coaxial cables, for example, is consequently no longer possible.
A possible solution of the inductance problem would be to attach the corresponding drive circuits on the gate side directly on top of the semiconductor substrate ("piggy-back" arrangement). However, this solution would have the following disadvantages:
excessive space requirement;
pressure contacts cannot be realized for components having a diameter &gt;1''; and
cooling of drive circuits at high frequencies, for example in a module, presents problems.